336 INORGANIC AGENTS 



Amyl nitrite is administered usually by inhalation to the larger 

 animals, from a sponge; or two or three drops are given by inhalation 

 from a bit of linen or cotton to the smaller animals. It may be given 

 internally on sugar to the smaller animals, or in spirit to the larger 

 patients. The spiritus glonoini is the only preparation of nitroglycerin 

 in use. It may be dropped undiluted upon the tongue of the conscious 

 or unconscious animal. The tongue of the smaller animals may be fre- 

 quently moistened with a small stick dipped in the solution, or it may be 

 given in pill or tablet. 



Class 4. — Chloral. 



Chloralum Hydkatum. (U. S. P.) 

 Chlokal Hydrate. Chloral. CjH CI3O-I-H2O. 



Synonym. — Chloral hydras, B. P.; hydrate of chloral, E.; chloratum hydratum 

 crystallisatum, P. G.; hydrate de chloral, Fr. ; chloralhydrat, G. 



A compound of trichloraldehyde, or chloral with one molecule of water. It 

 contains not less than 99.5 per cent, of CjH ClaO+H^O. 



Derivation. — Dry chlorine gas is passed into absolute alcohol until the latter 

 is saturated. Aldehyde and hydrochloric acid first result, C2H5O H+2 CI = 

 C2H4O+2 H CI. The chlorine gas then acts upon the aldehyde, abstracting 3 

 atoms of hydrogen and replacing 3 atoms of chlorine, and so forms chloral. 



CjHiO+e CI — CjH cia 0+3 H CI. 



Chloral is purified first by distillation with sulphuric acid, and then with 

 lime, and when mixed with water forms chloral hydrate (CjH CI3O+H2O). 



Properties. — Rhoinboidal, colorless and transparent crystals which do not 

 readily attract moisture. It has an aromatic, penetrating and slightly acrid 

 odor, and a bitterish, caustic taste. Slowly volatilized when exposed to the air. 

 Freely soluble in water, alcohol or ether; also in chloroform, benzol, benzin, car- 

 bondisulphide, fixed and volatile oils. It liquefies when triturated with about 

 an equal quantity of camphor, menthol, thymol or carbolic acid. Chloral is de- 

 composed by caustic alkalies, alkaline earths and ammonia, chloroform being 

 formed, and a formate of the base produced. 



Dose.—H. & C, gi-ii, (30-60) ; Sh. & Sw., 3i-ii, (4-8) ; D., gr. v-xx, (.8-1.8). 



Action External. — Chloral is a strong irritant applied locally in con- 

 centration to the skin and mucous membranes, owing to chlorine content, 

 and if injected under the skin may cause abscess and sloughing. It is a 

 powerful antiseptic, and relieves itching, especially in combination with 

 camphor. It has some local anesthetic action on sensory nerve endings. 



Action Internal. — Alimentary Canal. — Chloral produces severe irri- 

 tation of the mucous membrane in concentrated solution (20 per cent, or 

 over), and large doses may cause vomiting in dogs. The writer has seen 

 intense glossitis and stomatitis follow the breaking of a gelatine capsule, 

 containing chloral, in the mouth of a horse. Medicinal doses counteract 

 fermentation and flatulence in the digestive tract by its antiseptic action. 



Blood. — Chloral, absorbed into the blood, is reduced in part in the 

 tissues to trichlorethylalcohol, which combines with glycuronic acid to 

 form urochloralic acid. It was formerly thought that the action of chloral 

 was due to chloroform produced by the decomposition of the former in the 

 alkaline blood. C^H CI3 0+K H O = C H Clg-fK C H O^ (formic 

 acid). 



It is now known that the blood is not sufficiently alkaline to decom- 



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